The present invention relates to an image recording apparatus such as a digital camera or the like.
Conventionally, an image recording apparatus picks up an image by a photoelectric converter, e.g., CCD or the like, then performs image processing including compression processing, and records the image data in a recording medium such as a PC card, hard disc or the like. Assume a case of using an image recording apparatus of this type, wherein the processing speed of the CCD is the fastest, the processing speed of image processing is the next fastest, and the access speed of a recording medium, e.g., PC card or the like, is the slowest. In order for image sensing speed to not fall behind the CCD""s processing speed, a temporary storage may be provided in the process. As a method of providing a temporary storage, the following two methods may be considered.
 less than Method 1 greater than 
An image sensed by a CCD is stored in a temporary storage before image processing is performed. The image data is read out of the temporary storage and then image processing is performed while the processed image being written in a PC card.
 less than Method 2 greater than 
An image sensed by a CCD is stored in a temporary storage after image processing is performed. The image data is sequentially read out of the temporary storage and written in a PC card.
According to Method 1 of the above two methods, since a memory having the faster access speed than the CCD""s processing speed is generally available, it is possible to write image data, sensed by the CCD, in a temporary storage memory without reducing the CCD""s processing speed. However, because image data is temporarily stored before compression processing is performed, if the number of frames sensed serially is to be increased, a large memory capacity is required.
On the contrary, according to Method 2, since image data is stored in a temporary storage memory after image processing including compression processing is performed, a larger number of frames can be serially sensed and stored in the same memory capacity compared to Method 1. However, because the CCD""s processing speed depends upon the speed of image processing, if the image processing speed is slower than the CCD""s processing speed, the CCD""s processing capability cannot fully be utilized. Thus, the speed of serial image sensing according to Method 2 is slower than that of Method 1.
As described above, Method 1 is disadvantageous in terms of the number of frames sensed serially, and Method 2 is disadvantageous in terms of the speed of serial image sensing.
The present invention has been proposed to solve the above conventional problems, and has as its object to provide an image recording apparatus, image recording method and storage medium, which can increase the number of serially sensed frames and increase the speed of serial image sensing at low cost.
In order to solve the foregoing problems and attain the above object, an image recording apparatus of the present invention has the following configuration according to its first aspect.
More specifically, the image recording apparatus comprises: photoelectric conversion means for converting light from an object to an electric signal; first temporary storage means for temporarily storing data outputted by the photoelectric conversion means; image processing means for performing image processing, including compression processing, on the data read out of the first temporary storage means; second temporary storage means for temporarily storing the data, on which image processing has been performed by the image processing means; and recording means for recording the data, read out of the second temporary storage means, in a recording medium.
Furthermore, an image recording method of the present invention has the following configuration according to its first aspect.
More specifically, the image recording method comprises: a photoelectric conversion step of converting light from an object to an electric signal; a first temporary storage step of temporarily storing data obtained in the photoelectric conversion step; an image processing step of reading the data, stored in the first temporary storage step, and performing image processing, including compression processing, on the read data; a second temporary storage step of temporarily storing the data, on which image processing has been performed in the image processing step; and a recording step of reading the data, stored in the second temporary storage step, and recording the read data in a recording medium.
Furthermore, a storage medium of the present invention has the following configuration according to its first aspect.
More specifically, the storage medium storing a control program for controlling an image recording apparatus, said control program includes: program code means for a photoelectric conversion step of converting light from an object to an electric signal; program code means for a first temporary storage step of temporarily storing data obtained in the photoelectric conversion step; program code means for an image processing step of reading the data, stored in the first temporary storage step, and performing image processing, including compression processing, on the read data; program code means for a second temporary storage step of temporarily storing the data, on which image processing has been performed in the image processing step; and program code means for a recording step of reading the data, stored in the second temporary storage step, and recording the read data in a recording medium.
Furthermore, an image recording apparatus of the present invention has the following configuration according to its second aspect.
More specifically, the image recording apparatus comprises: photoelectric conversion means for converting light from an object to an electric signal; a first compression processor for compressing data outputted by the photoelectric conversion means; first temporary storage means for temporarily storing the data compressed by the first compression processor; a decompression processor for decompressing the compressed data read out of the first temporary storage means; first switch means for selectively transferring the data decompressed by the decompression processor, or the data on which decompression processing is not performed, to a circuit of the subsequent step; image processing means for receiving the data from the first switch means and performing image processing including second compression processing; second switch means for selectively transferring the data on which image processing has been performed by the image processing means, or the data on which image processing is not performed by the image processing means, to a circuit of the subsequent step; second temporary storage means for receiving the data from the second switch means and temporarily storing the received data; and recording means for recording the data, read out of the second temporary storage means, in a recording medium.
Furthermore, an image recording apparatus of the present invention has the following configuration according to its third aspect.
More specifically, the image recording apparatus comprises: photoelectric conversion means for converting light from an object to an electric signal; a first compression processor for compressing data outputted by the photoelectric conversion means; first temporary storage means for temporarily storing the data compressed by the first compression processor; a decompression processor for decompressing the compressed data read out of the first temporary storage means; image processing means for receiving the data from the decompression processor and performing image processing including second compression processing; second temporary storage means for temporarily storing two types of data: data which has been read out of the first temporary storage means and not processed by the decompression processor or the image processing means, and data which has been processed by the decompression processor and the image processing means; and recording means for recording the two types of data, read out of the second temporary storage means, in a recording medium.
Furthermore, an image recording method of the present invention has the following configuration according to its second aspect.
More specifically, the image recording method comprises: a photoelectric conversion step of converting light from an object to an electric signal; a first compression processing step of compressing data obtained in the photoelectric conversion step; a first temporary storage step of temporarily storing the data compressed in the first compression processing step; a decompression processing step of reading the compressed data stored in the first temporary storage step and decompressing the data; a first switching step of selectively transferring the data decompressed in the decompression step, or the data on which decompression processing is not performed, to a circuit of the subsequent step; an image processing step of receiving the data from the first switching step and performing image processing including second compression processing; a second switching step of selectively transferring the data on which image processing has been performed in the image processing step, or the data on which image processing is not performed in the image processing step, to a circuit of the subsequent step; a second temporary storage step of receiving the data from the second switching step and temporarily storing the received data; and a recording step of reading the data stored in the second temporary storage step and recording the read data in a recording medium.
Furthermore, an image recording method of the present invention has the following configuration according to its third aspect.
More specifically, the image recording method comprises: a photoelectric conversion step of converting light from an object to an electric signal; a first compression processing step of compressing data obtained in the photoelectric conversion step; a first temporary storage step of temporarily storing the data compressed in the first compression processing step; a decompression processing step of reading the compressed data stored in the first temporary storage step and decompressing the read data; an image processing step of receiving the data from the decompression processing step and performing image processing including second compression processing; a second temporary storage step of temporarily storing two types of data; data which has been stored in the first temporary storage step, then read out, and not processed in the decompression processing step or the image processing step, and data which has been processed in the decompression processing step and the image processing step; and a recording step of reading the two types of data stored in the second temporary storage step and recording the read data in a recording medium.
Furthermore, a storage medium of the present invention has the following configuration according to its second aspect.
More specifically, the storage medium, storing a control program for controlling an image recording apparatus, said control program includes: program code means for a photoelectric conversion step of converting light from an object to an electric signal; program code means for a first compression processing step of compressing data obtained in the photoelectric conversion step; program code means for a first temporary storage step of temporarily storing the data compressed in the first compression processing step; program code means for a decompression processing step of reading the compressed data stored in the first temporary storage step and decompressing the data; program code means for a first switching step of selectively transferring the data decompressed in the decompression step, or the data on which decompression processing is not performed, to a circuit of the subsequent step; program code means for an image processing step of receiving the data from the first switching step and performing image processing including second compression processing; program code means for a second switching step of selectively transferring the data on which image processing has been performed in the image processing step, or the data on which image processing has not been performed in the image processing step, to a circuit of the subsequent step; program code means for a second temporary storage step of receiving the data from the second switching step and temporarily storing the received data; and program code means for a recording step of reading the data stored in the second temporary storage step and recording the read data in a recording medium.
Furthermore, a storage medium of the present invention has the following configuration according to its third aspect.
More specifically, the storage medium, storing a control program for controlling an image recording apparatus, said control program includes: program code means for a photoelectric conversion step of converting light from an object to an electric signal; program code means for a first compression processing step of compressing data obtained in the photoelectric conversion step; program code means for a first temporary storage step of temporarily storing the data compressed in the first compression processing step; program code means for a decompression processing step of reading the compressed data stored in the first temporary storage step and decompressing the read data; program code means for an image processing step of receiving the data from the decompression processing step and performing image processing including second compression processing; program code means for a second temporary storage step of temporarily storing two types of data; data which has been stored in the first temporary storage step, then read out, and not processed in the decompression processing step or the image processing step, and data which has been processed in the decompression processing step and the image processing step; and program code means for a recording step of reading the two types of data stored in the second temporary storage step and recording the read data in a recording medium.
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.